COMPUTER STUDIES
MARKING SCHEME
FORM 1 END TERM 3 2022
- Using arrows, match the following generations of computers with the technology which they relied on.
GENERATION TECHNOLOGY
First Generation VLSI
Second Generation Thermionic valves
Third Generation ICs
Fourth Generation Transistors (4×1 marks)
- Give three advantages of the second generation computers.
- They were smaller in size compared to first generation.
- They more reliable.
- They generated less heat.
- They were less prone to hardware failure. (3×1 marks)
- Identify three major categories of computer hardware: (3×1 marks)
- Input devices
- Output devices
- Central Processing Unit
- Storage devices
- The illustrations below represent two orientations of a very important part of a desktop computer. Study them to answer the questions below:
- Name the object represented in the above images.
- System unit (1 mark)
- Identify the orientations represented in orientations A and B.
- A: Tower Orientation B: Desktop orientation (2×1 marks)
- Give four components that are houses inside the object represented in the above images.
(2×1 marks)
Random Access MEMORY
Central Processing Unit
CMOS battery
Expansion slots
Hard disk
Drives
Power supply unit
5) Give three reasons why a mobile phone is regarded to be a computer.
– It is electronic * uses electric energy to operate
– It has a display unit (screen)
– It has a keypad
– It has a memory for storage
– It is programmable
6. (a) Define the term ‘ computer laboratory’. (2mks)
– A computer laboratory is a room that has been specially prepared to facilitate installation of computers, and provide a safe conducive environment for teaching & learning of Computer studies.
(b) Give two factors to be considered when preparing a computer laboratory. (2mks)
– Security of computers
– Reliability of the source of power
– Number of computers to be installed and the amount of space available
– The maximum number of users that the laboratory can accommodate
7. a) List down three safety precautions one should observe when entering a computer laboratory. (3mks)
– Avoid smoking or exposing computers to dust
– Avoid carrying foods & drinks/ beverages to the computer room
– Avoid unnecessary movements as you may accidentally knock the peripheral devices
– Only authorized people should enter the computer room
– Computers users should be trained on how to use computers frequently
– Computer illiterates should not be allowed to operate the computers
– collect any waste papers which might be lying in the computer room & put them into the dustbin
– Shut the door of the computer room properly
b). Identify three facilities that will ensure proper ventilation in a room. (3mks)
– Large & enough windows and doors
– Installing fans
– Installing air conditioning system
– Avoid overcrowding of either machines or people in the room
8. State three reasons for warm booting your computer. (3 marks)
- During the installation of hardware for the drives to be activated.
- During the installation of a new software for the installation to complete.
- When a program encounters an error.
- When a computer hangs or fails to respond.
- When switching between operating systems.
9. (a) State two reasons why a computer needs to be connected to a stable power supply.(2mk)
– To prevent damage to the computer’s secondary storage media
– To avoid damage and loss of important data or information such as application software stored on the media
– Prevent loss of data/ information that had not been saved before the failure
(b) List down four functions of the uninterruptible Power Supply (UPS) (4mks)
– It prevents sudden power surges that might destroy the computer
– It supplies power to the Computer during blackouts and brownouts
– It provides stable (clean) power supply
– Alerts the user of power loss (by beeping)
– Allows the user to save his/ her work, and switch off the system using the correct procedure
10. Mention two things that are likely to cause strain- in the computer room
– Poor lighting of the room
– Bright monitors
– Flickering monitors
– Very bright wall paints reflect too much light
- (a) What is a peripheral device?
- They are connected to system unit using cables called data interface cables that carry data and information to and from the devices. (1 mark)
- Give three examples of common peripheral devices.
- Keyboard
- Mouse
- Monitor
- Printer (3×1 marks)
- What is the difference between analog and digital computers?
- Analog process data in continuous form while digital process data in discrete form. (2×1 marks)
- Give two reasons why smaller computers like laptops tend to be more expensive than desktop computers.
- The technology of producing smaller devices is expensive.
- Convenience because of their portability. (2×1 marks)
- Computers are classified using three criteria namely, functionality, purpose and physical size. In each of these classes, name and describe:
(a) Three types of computers under classification by functionality.
- Analog computers
- Digital computers
- Hybrid computers (3×2 marks)
(b) Three types of computers under classification by purpose.
- General purpose
- Special purpose
- Dedicated purpose (3×2 marks)
(c) Four types of computers under classification by physical size.
- Super computers
- Mainframe
- Mini computers
- Micro computers (4×2 marks)
- (a) Explain the meaning of the following mouse techniques:
(i) Clicking
- Means pressing and releasing the left mouse button once. (1 mark)
(ii) Dragging
- press and hold down left button and the move the mouse to the new location (1 mark)
(iii) Drop
- release the button immediately after dragging the item to the new location (1 mark)
(iv) Right clicking
- Pressing the right hand side mouse button once. (1 mark)
(b) Describe three categories of keys found on the keyboard.
- Functions keys – F1 to F12.
- Alphanumeric (Tying) keys – labelled A – Z, Caps lock, Enter keys, Tab key, Spacebar, backspace etc.
- Cursor movement (Navigation) & Editing keys – arrow keys, Page up and Page down, Home and end keys, Edit keys, Insert key, Delete
- Special keys – Shift, Ctrl, Alt, Esc etc.
- Numeric keys – 0 to 9, +, “, /, – (stating=1, describing/examples = 1, 3×2 marks)
(c) Describe the following terms as used in computers:
(i) Cold booting (1 mark)
- Cold booting is starting up a computer while.
(ii) Warm booting
- A computer that has been turned off but the previous state is stored for easy access of the work that one was previously doing. (1 mark)
(d) Define the following terms (5 marks)
(i) Information
- Refers to data which has been processed
(ii) Processing
- Refers to the way data is manipulated to turn into information e.g. arithmetic operation, addition subtraction etc.
(iii) Input
- What a computer receives as raw data to process
(iv) Data
- A mass of raw unprocessed facts
(v) Storage
- Saving of information for future reference
16. (a) What is a softcopy output? (1 mark)
Output that can be listened to or viewed. The output is not tangible.
(b) Give four differences between an impact and non-impact printer. (4marks)
| Impact | Non-impact |
| Speed of printing is slow | Speed of printing is high |
| Use inked ribbons, which may be black or colored | Use electrostatic or thermal principles |
| Multiple copy production is possible when carbonated paper is used | Multiple copy production is almost impossible |
| Cheaper to buy and maintain. The ribbons are not expensive. | Costly to purchase and maintain. The tonners and cartridges are expensive |
| Noisy printers | Quiet printers |
(c) Give five differences between a CRT and flat panel screen. (5 marks)
| CRT | Flat Panel Screen |
| It is bell shaped | The screen is flat shaped |
| Has poor resolution | Has a high resolution |
| Produces a high amount of radiation | Produces a low amount of radiation |
| Consumes more power | Consumes less power |
| Emit a lot of light | Emit very little light |
| Heavier, hence less portable | Light, hence portable |
| Occupies more space | Occupies less space. |
| Cheaper | Expensive |
(d) State five reasons why one may go for a hardcopy output. (5 marks)
- One may need to sign a document, for example a letter.
- One may need to read the work away from the computer.
- In anticipation of a power blackout.
- It is necessary for physical record keeping.
- One may want to scan, photocopy or fax a document.
- Some users have difficulties reading from the monitor, they experience eyestrain.
- Hardcopies are important backups in case the softcopy gets corrupted or the computer system crashes.
17. a) What do the following acronyms mean in full: (2mks)
i) VDU = Video Display Unit
ii) LCD = Liquid Crystal Display
iii) VGA = Video Graphics Adapter
iv) XGA.= Extended Graphics Array
b). State any five factors to consider when choosing a printer. 86 (5mks)
- Cost-
- Speed and the workload available
- Technology used – impact and non-impact
- Range of capabilities
c) i) Briefly define a computer bus. (2mks)
- It is a communication path within which the computer allows different elements of the computer to communicate with each other.
ii) Describe three types of computer buses. (6mks)
- Data bus
- Address bus
- Control bus
iii) What is a drive? (2mks)
- It is a computer device for reading data from or writing data into a storage media.
iv) State four types of computer drives. (4mks)
- Hard disk drive
- Floppy disk drive
- USB port
- CD-ROM drive
- DVD-ROM drive
- Zip drive
